1. Field of Invention
The invention relates to coin dispensers, and in particular to automatic coin dispensers for selectively dispensing coins in order to make change. Such coin dispensers are often found, for example, at checkout counters of grocery stores and at the cashier of restaurants, convenience stores, etc., although they have numerous other applications.
2. Description of Related Art
The most common type of coin dispenser for use, for example, in grocery stores or in other applications in combination with a checkout counter or cashier, has a series of vertically extending coin holding tubes that are arranged in a line. Examples of such coin dispensers are shown, for example, in U.S. Pat. Nos. 3,590,833 and 4,593,709.
While being popular and reliable, these coin dispensers are mechanically complicated and, therefore, are expensive due to the large number of parts and the large amount of time required to manufacture such dispensers. This is because a separate actuator (e.g., a solenoid) must be provided for each coin-holding tube. Thus, a coin dispenser having nine coin tubes requires at least nine separate actuators.
Additionally, because the plurality of coin tubes are arranged in a line and are stationary, an inclined ramp must be provided below the line of coin-holding tubes so that the coins ejected from the various tubes will be conveyed, by gravity, to a coin-receiving cup. The requirement for this inclined ramp increases the height of the dispenser, further increasing its size and weight.
U.S. Pat. Nos. 3,191,609 and 4,276,894 disclose arrangements in which a single actuator is used to selectively eject coins from a plurality of coin tubes.
The arrangement disclosed in U.S. Pat. No. 3,191,609 includes a stationary housing in which a plurality of vertical tube-like coin containers are arranged in a circle or oval. A central rotary part includes a single actuator having a carrier pin that is selectively extended and retracted. As the rotary part rotates beneath each of the coin containers, the actuator is selectively energized in order to dispense coins from the containers. The rotary part also includes a coin collecting tray into which the coins that are to be dispensed fall. The actuator is movably mounted, and biased into its normal position by a torsion spring, so that the actuator can move out of its normal position without being damaged in the event that there is a jam condition. Because the coin collecting tray rotates with the rotary part, the rotary part must come to a complete stop at a particular position relative to the housing so that the coins located in the coin collecting tray can be accessed through an opening in the housing. This increases the amount of time required to complete a coin dispensing cycle because the rotary part must be brought to a complete stop at a predetermined position before the coins are dispensed.
The arrangement disclosed in U.S. Pat. No. 4,276,894 mounts a plurality of vertical coin tubes, arranged in a circle, on a rotatable base. As the base rotates, the coin tubes selectively become aligned with a coin ejecting mechanism which can be activated in order to eject a coin from that tube. The coin ejecting mechanism includes a pin that moves radially outward with respect to the rotatable base in order to eject a coin from a selected coin tube. This arrangement requires precise timing between the rotation of the rotatable base and the radial movement of the pin, and therefore includes a complicated gear arrangement.
Accordingly, there is a need for an improved coin dispenser that has a relatively simple construction, and therefore a lower manufacturing cost, and that also is relatively compact in size.
According to one aspect of the invention, a coin dispenser includes a rotatable magazine and a stationary actuator that is operative to eject coins from the rotatable magazine. The magazine rotates about a rotation axis and includes a plurality of coin receptacles extending substantially parallel to the rotation axis. Each coin receptacle holds a stack of coins. The stationary actuator includes a coin-ejection member that moves linearly in a direction substantially parallel to the rotation axis of the rotatable magazine between an extended position and a retracted position. When the coin-ejection member is in its extended position, it will engage the outer edge of at least a lowermost coin in a specified one of the coin receptacles as the magazine rotates, and therefore will eject that coin out of the coin dispenser.
A lowermost portion of each coin receptacle includes a coin-ejection slot through which at least a lowermost coin in that receptacle is ejected from the rotatable magazine as the receptacle is conveyed past the coin-ejection member when in the extended position. Preferably, each of the coin-ejection slots includes a longitudinal axis that extends at a non-zero angle relative to a radial direction of the magazine. This reduces the possibility of coins being accidentally ejected from the magazine due to centrifugal forces caused by rotation of the magazine.
Preferably, each of the coin-ejection slots has an outlet on a radially outer surface of the rotatable magazine. It is, of course, possible to provide the outlet on a radially inner surface of the rotatable magazine. However, providing the outlets on the radially outer surface of the magazine enables the overall height of the coin dispenser to be minimized since it would be necessary to provide a ramp in order to direct coins to the outlet of the coin dispenser if the coins were ejected radially inwardly from the magazine.
In a preferred embodiment, the coin dispenser includes a stationary base and a drive motor mounted to the stationary base. The drive motor includes a drive gear that removably couples to and rotates the rotatable magazine about the rotation axis when the magazine is mounted to the stationary base.
In a preferred embodiment, the stationary actuator includes a single electro-mechanical actuator (e.g., a solenoid). More preferably, the drive motor and the single electro-mechanical actuator are the only electro-mechanical drive mechanisms included in the coin dispenser. Accordingly, the coin dispenser requires only two electro-mechanical drive mechanisms, thereby reducing its costs.
Preferably, the stationary actuator includes a torsion-resistant mount that permits the coin-ejection member to deflect if a coin that is to be ejected from the magazine becomes jammed in the magazine. This functions as a fail-safe mechanism, and prevents the coin ejection mechanism from being damaged.
Preferably, a single low-coin detector, such as, e.g., a photo-detector or a proximity sensor, is provided to detect whether the supply of coins in any of the receptacles is low. The machine can then avoid selecting receptacles having a low supply (for example, if one quarter receptacle is low, a different quarter receptacle is selected, or two dime receptacles and one nickel receptacle are selected), and/or provide an audible or visual alarm indicating that the magazine should be replaced.
According to one embodiment, the floor plate of the magazine includes a recess for each receptacle, onto which the lowermost coin in each receptacle rests. Preferably, the depth of each recess is determined based upon the thickness of the type of coin to be dispensed from that receptacle so that the upper surface of the lowermost coin in all receptacles are located in a common plane. The coin-ejection member includes an upper shoulder and a pin that extends upwardly from the shoulder. The floor plate includes a groove through which the pin extends when in its extended position, and a lower planar surface that is engaged by the shoulder when the coin-ejection member is extended. This arrangement results in the uppermost portion of the pin being maintained a predetermined distance below the coin that rests on top of the lowermost coin in each receptacle, so that only the lowermost coin is ejected. In addition, by selecting an appropriate depth of a recess, the pin can be made to contact the two lowest coins in a receptacle so that two coins can be ejected simultaneously from one receptacle.